java動態代理Dynamic Proxy

1.被代理對象的介面:

package test.dynamicproxy;public interface TargetInterface {public void SayHello();public int sum(int a ,int b);}

 

2.被代理的對象:

package test.dynamicproxy;public class Target implements TargetInterface {public void SayHello(){System.out.println("Hello");}public int sum(int a, int b) {return a+b;}}

 

3.InvocationHandler封裝:

package test.dynamicproxy;import java.lang.reflect.InvocationHandler;import java.lang.reflect.Method;public class TargetInvocationHandler implements InvocationHandler {private Object object;public TargetInvocationHandler(Object obj){this.object=obj;}public Object invoke(Object proxy, Method method, Object[] args2)throws Throwable{doBefore();Object result = method.invoke(object, args2);doAfter();return result;}public void doBefore(){System.out.println("do before");}public void doAfter(){System.out.println("do after");}}

4.測試類別:

package test.dynamicproxy;import java.lang.reflect.Proxy;public class TestDynamicProxy {/** * @param args */public static void main(String[] args) {Target t=new Target();TargetInvocationHandler handler=new TargetInvocationHandler(t);TargetInterface proxy = (TargetInterface) Proxy.newProxyInstance(t.getClass().getClassLoader(),t.getClass().getInterfaces(),handler);proxy.SayHello();int b=proxy.sum(10, 20);System.out.println(b);}}